Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 63. (Budapest 1971)

Kovács, L.: Data to the knowledge of Hungarian Macrolepidoptera VI. Data with respect to migrating and spreading species

II. The territorial occupations of spreading lepidopterous species in the Hungarian faunal region In the first part of the present paper I discussed lepidopterous species which depart far from their sites of breeding and which may transitionally settle in new localities during their wanderings but whose subsequent populations are unable to overcome the unfavourable conditions prevailing there. The spreading of lepidopterous species have other collateral phenomena. Spreading species cannot attain by far as great distances, during the same time, as the wandering lepidoptera. In all probability there is only a single known case in which a species invading Hungary has permanently occupied almost all suitable points of our faunal territory in the course of one year. The species in question, Libythea celtis LAICH, has, however, a very strong musculature and is an excellent flier (KOVÁCS, 1955). Spreading is in the majority of cases a slow process, advancing step by step, and may take decades until it comes to rest (KOVÁCS, 1955). In my paper cited above, I have discussed the circumstances of the occupational process of three species, having relegated two of them among the slowly spreading ones. Their route of advance could, however, be plotted only by the aid of occasional collectings at that time, hence inferences were valid only within wide limits. Since the nationwide light trap network was successfully organized, the possibilities of observing the spreading of lepidopterous species became incomparably better, as shown also by the following examples. I propose to discuss the occupation of new regions by two Geometrids. Although the spreading of the first one came initially to our attention not by the aid of the light traps, it soon appeared in their ring and they presently played a decisive role in the registration of the further data. I have naturally continued to take advantage of also the reliable data of individual collectings, in order to trace the process as detailedly as possible. The second case was noted by the aid of the light traps. Though the advance of this species started only recently and the obtained data are restricted, some inferences can already be made. Future observations may also be instigated by the promulgation of our data to a wider public. 1. Lygris mellinata F. Neither the Fauna Regni Hungáriáé nor ABAFI-AIGNER'S book cite a home locality of this species. According to older data, it was collected near Eperjes and on the Branyiszkó (ABAFI-AIGNER, J. PÁVEL, N. UHRYK, 1896; ABAFIAIGNER, L., 1907). The first collector to show it from the present area of Hungary was J. GYŐRFI (Sopron, 10 June, 1956). The advance of the species is shown by the light traps since 1959. The earlier data of its gaining ground in Hungary are discussed, on my suggestion, by L. ZWICK in her Doctorate thesis (MS deposited in the Zoosystematical Institute of the L. Eötvös University of Sciences, Budapest). Unfortunately, these data remain as yet unpublished. Since then, numerous new data became available, and as the problem also has a background af applied interest, the situation is now ripe to call the interest of also the concerned parties to the case. According to literature data, the nearest locality of occurrence of L. mellinata, known since long, is the Marchfeld, not far from Sopron (STERZL, 1967). There is hardly any doubt that its recent spreading towards the east began from this region. It can be established that the advance took two routes: it was first reported from 17 TT. Múzeum Évkönyve 1971